1. Field of the Invention
This invention relates to electrical motors, their method of assembly, and contacts incorporated therein.
2. Summary of the Prior Art
As the number of electrical appliances increases, the need to manufacture and assemble small electrical motors in an efficient manner greatly increases. The motors are typically incorporated into appliances such as vacuum cleaners, kitchen appliances, and any other power accessory used in home or business. One electrical contact that is particularly useful for automated assembly is the Applicant's Mag-Mate Interconnection System. Contacts of this type enable insulation displacement-style contact techniques to be applied to magnet wire terminations, thereby eliminating the need for pre-stripping the magnet wire.
With particular respect to electrical motors, after winding the coils, the magnet wire is placed across a plastic cavity and retained therein by a slight frictional fit. The magnet wire is supported by part of the housing such that as the contact is inserted into the plastic cavity, the magnet wire is guided into the terminal slots of the contact. As the contact is seated, the film insulation upon the wire is striped and further insertion results in the bare wire coming in contact with contact surfaces within the slot. As the contact is being pressed within the cavity, locking barbs upon the contact bite into the plastic cavity assuring terminal retention.
In order to interconnect with a mating lead, various means for lead connection have been provided, such as poke-in latches for directly receiving the wire, tabs for receptacle terminals, posts for wrapping wire thereabout, wire barrels or solder tabs. Contacts of this type have preformed admirably and offer many advantages. However, as the industry becomes more and more sophisticated, it becomes necessary to provide electrical contacts that further enhance the assembly processes capability to be automated.
What is needed is an electrical contact incorporating the advantages outlined above, wherein the interconnection with the wire lead does not require a separate step. It would be advantageous if this interconnection could be formed in some sort of wiping manner. It would further be desirable to take advantage of this interconnection offered by the contact to provide an improved assembly technique that would enable further application of robotic assembly techniques to electrical motors. In particular, it would be desirable to enable the electrical brushes to be assembled with the motor unit in a first preassembled position where the motor shaft carrying the motor windings and the commutator thereupon may be inserted into the coil cavity by robotic techniques, afterwhich the brush assemblies could be displaced into their final position, such that the electrical connection between the lead and the magnet wire is established.